Webflags: g

XML Processing Instruction

Match XML processing instructions like `<?xml version="1.0" encoding="utf-8"?>` or `<?xml-stylesheet href="..."?>`.

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Available in

JSSupported

JavaScript / ECMAScript

Browser-native RegExp. Default if you don't pick.

PYSupported

Python (re)

CPython stdlib `re`. Unicode-aware `\w` and `\d` by default.

GOSupported

Go (RE2)

Linear-time matching. No backreferences or lookarounds.

Pattern

regexengine-agnostic
<\?[\w\-]+(?:\s+[\w\-]+\s*=\s*["'][^"']*["'])*\s*\?>   (flags: g)

Raw source: <\?[\w\-]+(?:\s+[\w\-]+\s*=\s*["'][^"']*["'])*\s*\?>

How it works

<\? matches the literal opener. [\w\-]+ captures the PI target name. The repeating group matches optional `attr="value"` pairs. The trailing `\s*\?>` matches the closer. Works for the XML declaration and any custom processing instruction.

Examples

Input

<?xml version="1.0" encoding="UTF-8"?>

Matches

  • <?xml version="1.0" encoding="UTF-8"?>

Input

<?xml-stylesheet type="text/xsl" href="style.xsl"?>

Matches

  • <?xml-stylesheet type="text/xsl" href="style.xsl"?>

Input

<root>plain</root>

No match

—

Common use cases

  • •XML/SVG/RSS preprocessing
  • •Detecting and stripping XML declarations before merging documents
  • •XSLT pipeline tooling
  • •Sitemap and feed validation

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Match CSS custom properties (variables) like `--brand-color` or `--font-size-lg`.

Cookie Header Value

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Parse name=value pairs from an HTTP `Cookie:` header value.

CSS Class from `class=""` Attribute

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Extract the value of a `class="..."` attribute from raw HTML, handling double or single quotes.

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